Primers of selected genes were designed using PrimerQuest tool of Integrated DNA Technologies (Integrated DNA Technologies, Inc., California, US) and are shown in Additional file 1: Table S1. Power SYBR Green PCR Master Mix (Takara, Kusatsu, Japan) was used for real-time PCR in Applied Biosystems 7900HT Fast Real-Time PCR System as per the manufacturer’s suggestion. The reaction procedure was as follows: incubation at 95 °C for 10 min followed by 40 cycles of 95 °C for 10 s, 49 °C for 15 s and 60 °C for 45 s. Three independent reactions were conducted with triplicates for each gene and reaction mixture without RNA template was used as negative control for each set of primers. Expression analysis of each gene was calculated based on at least two independent experiments. Melting curve analysis was done to verify primer specificity and relative expression values were calculated as 2-∆(CT Target - CT reference) with 23S rRNA gene as housekeeping gene.